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Investments in fixed maturity securities | 9 Months Ended
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Sep. 30, 2025
Investments, Debt and Equity Securities [Abstract] |
Investments in fixed maturity securities | Note 3. Investments in fixed maturity securities Investments in fixed maturity securities are summarized as follows (in millions).
|  | Amortized Cost |  |  | Unrealized Gains |  |  | Unrealized Losses |  |  | Fair Value |
September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury, U.S. government corporations and agencies |  | $ | 4,613 |  |  | $ | 13 |  |  | $ | — |  |  | $ | 4,626 |
Foreign governments |  |  | 11,822 |  |  |  | 39 |  |  |  | (19 | ) |  |  | 11,842 |
Corporate and other |  |  | 1,240 |  |  |  | 239 |  |  |  | (4 | ) |  |  | 1,475 |
|  | $ | 17,675 |  |  | $ | 291 |  |  | $ | (23 | ) |  | $ | 17,943 |
December 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |
U.S. Treasury, U.S. government corporations and agencies |  | $ | 4,447 |  |  | $ | 16 |  |  | $ | (4 | ) |  | $ | 4,459 |
Foreign governments |  |  | 9,443 |  |  |  | 16 |  |  |  | (97 | ) |  |  | 9,362 |
Corporate and other |  |  | 1,324 |  |  |  | 225 |  |  |  | (6 | ) |  |  | 1,543 |
|  | $ | 15,214 |  |  | $ | 257 |  |  | $ | (107 | ) |  | $ | 15,364 |
As of September 30, 2025, approximately 95% of our foreign government holdings were rated AA or higher by at least one of the major rating agencies. The amortized cost and estimated fair value of fixed maturity securities at September 30, 2025 are summarized below by contractual maturity dates (in millions). Actual maturities may differ from contractual maturities due to prepayment rights held by issuers.
|  | Due in one year or less |  |  | Due after one year through five years |  |  | Due after five years through ten years |  |  | Due after ten years |  |  | Mortgage- backed securities |  |  | Total |
Amortized cost |  | $ | 12,780 |  |  | $ | 4,179 |  |  | $ | 498 |  |  | $ | 109 |  |  | $ | 109 |  |  | $ | 17,675 |
Fair value |  |  | 12,829 |  |  |  | 4,179 |  |  |  | 693 |  |  |  | 120 |  |  |  | 122 |  |  |  | 17,943 |

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